How to Evaluate Rock Drill Manufacturers: The Checklist I Use Before a Rig Goes Underground

I'm a field support specialist at Sandvik Mining and Rock Solutions. If you've been searching for 'Sandvik mining and construction' equipment, you're in about the right place—that heritage now sits inside Sandvik Mining and Rock Solutions, and the focus on rock drills and the support around them hasn't changed. For the past eight years, I've spent most of my working hours helping mining and aggregate teams get rock drills back online—usually because someone in the value chain bought an impressive machine and then discovered the support network was thinner than the brochure suggested.

So here's the conclusion up front: Stop choosing a rock drill manufacturer by spec sheet torque and feed force alone. When you're shortlisting a drilling rig supplier, the same logic applies. Specs are entry-ticket numbers. The decision that actually keeps a mine producing is what happens after the machine breaks.

Why does this matter? Because downtime on a drill is never just one machine. The drill stops, the blast doesn't happen, the next development round slips, and then the loaders and crushers sit waiting. In my role, I've seen the full cost of that chain—not just the repair invoice.

In March 2024, a customer called at 10 a.m. with a production drill rig down and a face blast scheduled for 36 hours later. Normal lead time for the failed hydraulic cylinder was ten days. That wasn't going to work. We found a remanufactured cylinder in a regional warehouse, paid about $3,000 in urgent freight, and had the rig drilling again in 31 hours. The customer's alternative was an idle blast block and a chain of delays that would probably have hit several hundred thousand dollars in deferred development.

That example isn't a pitch for heroics. It's the reason I tell every procurement team to evaluate a drilling rig supplier by the aftermarket plan, not only the machine. Here's the checklist I actually use.

The Checklist I Actually Use

1. Put the critical parts list on the table

The first question isn't 'how many drills do you sell?' It's 'where are the spares for this specific model stocked?'

Ask for a list of critical wear parts: shank adapters, accumulators, seals, pressure sensors, hydraulic hoses, and anything else that stops a drill in its tracks. Then ask where each one is available and what the documented dispatch time is. If the answer is 'we'll need to check with the central warehouse,' walk away. A parts list with no location is just a wish list.

Look for a supplier that can name the warehouse, the stock level, and the normal dispatch window. It doesn't have to be perfect—no one stocks everything at every site. But the difference between 'we'll check in the morning' and 'there are six in the Houston hub, and dispatch runs at 4 p.m.' is the difference between a support culture and a ticket queue.

2. Test the support line before you sign

Vendor selection often ends with a nice site visit. So schedule a test after the sales deck. Call the after-hours parts line at 4:30 p.m. on a Friday and ask something deliberately vague, like 'what's the service interval for a DTH hammer on a 3-inch hole?'

See how long it takes to get a human. Ask for an installation drawing or an air filter cross-reference. A supplier that treats a pre-sales question as annoying is not going to magically become responsive when there's a failed accumulator underground at midnight.

The question isn't whether their sales responsiveness is good. It's whether their service desk is good.

3. Insist on drilling data from ground like yours

It's tempting to think that any granite is close enough to any other granite. That's the classic simplification, and it's exactly how a lot of bad purchasing decisions get made. Rock hardness, fracture frequency, and abrasiveness change everything about a rock drill or drill string choice.

A reputable manufacturer should be able to share penetration rates, tool life, and energy consumption from sites with ground conditions similar to your mine. If they can only show generic marketing curves, that's a red flag.

What I mean is not that you need a guarantee of performance—anyone who guarantees penetration rates on unknown rock is guessing. But a supplier with real engineering behind them can point to case data, explain why it does or doesn't transfer to your site, and tell you honestly where the risk sits.

4. Compare the cost of the system, not the rig

A drilling rig is the gate fee. The recurring monthly cost is usually in drill steel, bits, grease, filters, maintenance plans, and—critically—the time it takes to get those items replaced.

Every time I see a mine choose a cheaper rig with the same rated output, the conversation usually shifts to consumable life within six months. A machine that runs a little slower but uses longer-lasting drill steel and is supported by local stock can be far cheaper per meter than a slightly faster machine that eats tooling and waits for parts.

So ask for a cost-per-meter model. If the supplier won't open their assumptions, treat it as a sign they don't have data to defend.

5. Ask what the warranty process actually involves

Warranties are easy to sell and hard to collect. Ask for the step-by-step claim path. How many photos are required? Who can return a failed part? Is there a provisional replacement policy for common failures, or do you have to wait for failure analysis before anything ships?

In my experience, the best support teams pre-ship a replacement while the return part is in transit, and handle the failure analysis after the mine is back up. That's not standard, and it's worth putting in the evaluation.

The Spec Sheet Trap

I get why people start with specs. They're clean, comparable, and easy to put into a spreadsheet. But the side-by-side comparison hides the most important variable: the gap between a drill that's designed for high average performance and one that's engineered for uptime in your conditions.

To be fair, specs are not meaningless. Feed force, torque, percussion power, and hole diameter bound the problem. But once half a dozen suppliers all show similar numbers, the differentiator is almost never the number. It's how the manufacturer behaves when the numbers don't move rock.

That's also why certifications matter. A rig designed under ISO 12100:2010 and CE-marked under the EU Machinery Directive 2006/42/EC has passed through a formal risk-reduction process. It doesn't tell you which brand is best, but it tells you which suppliers have done the basic engineering homework. Reference: ISO 12100:2010 and EU Machinery Directive 2006/42/EC. A team that can talk specifically about those standards usually has a better engineering culture than one that can only wave at a brochure.

To be fair, independent aftermarket and private-label parts suppliers sometimes have better stock on a single SKU than the original manufacturer. That's a real advantage in a pinch. Just verify the material grade, part dimensions, and the impact on your warranty before using them. The goal is informed decisions, not blind loyalty.

What Changed For Me: A 48-Hour Buffer

After the March 2024 save, our team changed the rule for critical hydraulic cylinders. For the top 30 rock drill parts, we keep a regional safety stock hard floor and review it quarterly. We also set a 48-hour buffer for any part that sits on the critical list for more than two sites.

I'm not a logistics expert, so I can't speak to the best way to optimize a global supply chain. What I can tell you from an aftermarket perspective is that those 31 hours felt sustainable because we had options and inventory. Without the buffer, even the best courier would have been too late. The buffer is the actual product.

When This Framework Doesn't Apply

If you're buying a single used drill for a small aggregate pit, this checklist is overkill. The local dealer relationship and the machine's immediate condition matter more than a global manufacturer's warehouse network. Choose the person who shows up on a Saturday.

If you're in a country with strict import rules, local stock and local service trump everything else. A global logistics network doesn't help if the customs clearance process takes three weeks. In that situation, ask about local assembly, local parts kits, and distributors with their own repair shop.

And if you're planning a new underground mine, get a rock mechanics consultant and an orebody-specific study before you talk to any drilling rig supplier. I can help with support and aftermarket architecture, but I'm not the right person to define the drill plan for your geological model. That's a specialist's job.

So when someone asks me which rock drill manufacturer to choose, my answer comes back as a question: what happens when the drill stops? If the supplier can't answer that with specifics—warehouse locations, dispatch windows, response capacity—keep looking. The machine is just the start of the relationship.